In a manufacturing process of a semiconductor device or a manufacturing process of a flat panel display (FPD), a process of supplying a processing liquid to various substrates such as a semiconductor wafer or a glass substrate to perform processing has been widely used. The process may include, for example, cleaning by various processing liquids, which is used to remove particles attached onto the surface of the substrate or a native oxide film formed by contacting the atmosphere.
As a liquid processing apparatus that performs the process such as the cleaning process of a substrate, an apparatus including, among others, a plurality of single wafer type liquid processing units and a transportation device is used. The transportation device carries in and out the substrate for the liquid processing units.
The liquid processing unit includes, for example, a rotation placement section, a processing liquid supply nozzle, and a rinsing liquid supply nozzle (see, for example, Japanese Patent Application Laid-Open No. H09-38595). The rotation placement section is rotatably installed while holding the substrate. The processing liquid supply nozzle supplies the processing liquid to the substrate and the rinsing liquid supply nozzle supplies the rinsing liquid to the substrate. The liquid processing unit holds the substrate such as the semiconductor wafer in the rotation placement section and performs the processing by supplying the processing liquid to, for example, the substrate surface while rotating the substrate. After the processing by the processing liquid, the rinsing liquid is supplied to the substrate surface while rotating the substrate to perform rinsing.
However, a liquid processing method in the liquid processing apparatus has the following problems.
For example, as the semiconductor device is miniaturized, a hole having a high aspect ratio which is a ratio of a depth to a diameter or a pattern having the high aspect ratio may be formed on the surfaces of various substrates such as the semiconductor wafer. There is a case where the substrate with the hole or pattern having the high aspect ratio is processed by a processing liquid and thereafter, the substrate is rinsed with rinsing liquid.
However, when the aspect ratio of the hole or pattern is high, even though the rinsing liquid is supplied to the substrate to which the processing liquid was previously supplied after the processing by the processing liquid, the processing liquid that remains in the hole or pattern cannot be easily substituted with the rinsing liquid. Therefore, after the rinsing, the processing liquid may remain in the hole or pattern. A rinsing time should be increased in order to prevent the processing liquid from being remained in the hole or pattern.
The above problems are not limited to the case where the substrate with the hole or pattern having the high aspect ratio formed on the surface thereof is processed by the processing liquid, and thereafter, rinsed. Even though the aspect ratio is not high, the processing liquid may be easily remained and the rinsing time may need to be increased. Accordingly, the problems are common ones that occur when various substrates with the hole or pattern formed on the surfaces thereof are processed by the processing liquid and thereafter, rinsed with rinsing liquid.